dimtel
dimtel
9.8
Memory
A custom driver designed for interfacing to Dimtel, Inc. longitudinal
front/back-end units (FBE) is selected when bit 16 of the main control reg-
ister is set to 1. The custom driver is included in the gateware starting from
version 1.4. Front and back-end phase settings control carrier phases in the
front and the back-end respectively. Offset-binary DAC setting in each case
provides adjustment range of
≈
400 degrees at the carrier frequency. Front
and back-end attenuation settings are in 0.5 dB steps for a total range of
31.5 dB.
Table 17: FPGA registers: Front/back-end GPIO
Address
Bits
Definition
0x00013c
11:0
Front-end phase
0x00013d
11:0
Back-end phase
0x00013e
5:0
Front-end attenuation
0x00013f
5:0
Back-end attenuation
9.8
Memory
iGp-5120F is configured with two data acquisition memory spaces: block-
RAM internal to the FPGA and external SRAM. Memory address mapping
is provided in Table 18.
Table 18: Data acquisition memory
Address range
Definition
0x010000-0x017fff
32k
×
32 blockRAM (128 ksamples)
0x800000-0xa00000
2M
×
32 SRAM (8 Msamples)
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